Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments - Summary of Changes in Fair Value of Company's Earn-Out Liability (Details)

v3.20.2
Fair Value of Financial Instruments - Summary of Changes in Fair Value of Company's Earn-Out Liability (Details) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Earn-out payments during the period $ 2,939 $ 2,497
Level 3 Inputs    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 9,154  
Earn-out payments during the period (3,231)  
Changes in fair value during the period (969)  
Ending balance 4,954  
MUSA-Stainless | Level 3 Inputs    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 2,403  
Earn-out payments during the period (1,263)  
Changes in fair value during the period (415)  
Ending balance 725  
MUSA-Galvanized | Level 3 Inputs    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 1,782  
Earn-out payments during the period (488)  
Changes in fair value during the period (38)  
Ending balance 1,256  
American Stainless | Level 3 Inputs    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 4,969  
Earn-out payments during the period (1,480)  
Changes in fair value during the period (516)  
Ending balance $ 2,973